Many systems use switching power converters to generate regulated voltages for components of the systems. In a buck or step-down converter, the converter generates an output voltage that is lower than its input voltage. In a boost or step-up converter, the converter generates an output voltage that is higher than its input voltage. In a buck-boost converter, the converter generates an output voltage that is lower or higher than its input voltage depending on its mode of operation.
In these types of converters, pulse width modulation (PWM) modulators are often used to convert control signals into duty cycle commands. For example, if a converter needs to decrease its output voltage, the PWM modulator may decrease the duty cycle of the duty cycle command in response to a control signal. If the converter needs to increase its output voltage, the PWM modulator may increase the duty cycle of the duty cycle command in response to a control signal.
A problem in conventional switching power converters is that transients in a regulated voltage can occur, such as loading transients caused by changes in a load that receives the regulated voltage. While a conventional switching power converter can typically operate to counteract loading transients, the converter's reaction time to the loading transients can be quite slow.